/Engine/Source/Developer/SkeletalMeshUtilitiesCommon/Public/LODUtilities.h
Before building skeletalmesh base LOD (LOD index 0) using MeshUtilities.BuildSkeletalMesh, we want to adjust the imported faces material index to point on the correct sk material. We use the material name to match the material.
static void AdjustImportDataFaceMaterialIndex ( const [TArray](API\Runtime\Core\Containers\TArray)< [FSkeletalMaterial](API\Runtime\Engine\Engine\FSkeletalMaterial) > & Materials, [TArray](API\Runtime\Core\Containers\TArray)< [SkeletalMeshImportData::FMaterial](API\Runtime\Engine\Rendering\FMaterial) > & RawMeshMaterials, [TArray](API\Runtime\Core\Containers\TArray)< [SkeletalMeshImportData::FMeshFace](API\Runtime\Engine\Rendering\FMeshFace) > & LODFaces, int32 LODIndex )